Used as a chromogenic substrate in enzymatic assays, particularly for detecting and quantifying peptidase activity. The compound is cleaved by specific enzymes, releasing a colored or fluorescent product that can be measured spectrophotometrically or fluorometrically. Its 4-methoxy-β-naphthylamine group provides a detectable signal upon hydrolysis, making it useful in diagnostic applications and biochemical research for monitoring enzyme kinetics and inhibition. Commonly employed in studies involving proline-specific peptidases, such as dipeptidyl peptidases.